Logical signal receiving circuitry, logical level converting circuitry, and input-output circuit isolating circuitry have been well known for decades. As the art relating to the logic of information handling systems and logical circuitry therefore has advanced, the requirements for logical signal translating circuitry has become more and more exacting. The circuitry according to the invention is concerned with the translation of logical signal levels from a relatively wide voltage swing to a relatively small voltage swing for use in binary current-switch logical circuitry. It is also concerned with obtaining a high degree of isolation between the input circuit and the output circuit, together with maintaining a high degree of stability.